SharedPtr.h


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#ifndef SHAREDPTR_H_
#define SHAREDPTR_H_

template <class T>
class SharedPtr {
  private:
    class Counter {
      public:
        Counter(T *o) : object(o), refCount(1) {}
        ~Counter() {delete object;}
        
        T *object;
        unsigned int refCount;
    };
    
    Counter *counter;
    
  public:
    SharedPtr(T *o) : counter(new Counter(o)) {}
    
    SharedPtr(const SharedPtr<T> &c) : counter(c.counter) {
      counter->refCount++;
    }
    
    virtual ~SharedPtr() {
      if(--counter->refCount == 0)
        delete counter;
    }
    
    SharedPtr<T>& operator=(const SharedPtr<T>& c) {
      c.counter->refCount++;
      if(--counter->refCount == 0)
        delete counter;
      
      counter = c.counter;
      return *this;
    }
    
    T* operator->() {return counter->object;}
    T& operator*() {return *counter->object;}
    
    const T* operator->() const {return counter->object;}
    const T& operator*() const {return *counter->object;}
};

#endif /*SHAREDPTR_H_*/